Keyboard organization



June 3 1969 T. s. I DUCA y 3,447,414

KEYBOARD ORGANIZATION Filed Nov. 4. 1966 Z nl o o 5%.2 zo 26 "2 3.., 40 38 4 y2 90 52 f za., 4-

A'rTofzNEs United States Patent Oflice 3,447,414 Patented June 3, 1969 3,447,414 KEYBOARD ORGANIZATION Thomas S. Lo Duca, 2232 S. 62nd St., Milwaukee, Wis. 53219 Filed Nov. 4, 1966, Ser. No. 592,216 Int. Cl. Gc 3/12 U.S. Cl. 84 436 5 Claims ABSTRACT OF THE DISCLOSURE The invention contemplates that prefabricated keys of appropriate color and design will be individually mounted permanently upon separately fabricated levers. At the front of the keyboard,`each key has an integral portion interlocked with a notch at the end of the lever. The rear end of the key is then riveted to the lever as a permanent assembly. The lever has the form of ai channel which is pivoted near its rear end to a base and which, at its forward end, must be guided for precise movement in a predetermined plane and for a predetermined range in that plane.

Regardless of the specific form of the key or its specilic mode of connection with the free end of the lever, the invention involves an arrangement whereby a cavity is provided in the manually engaged portion of the key at the free end of the lever and such cavity may be loaded with mass-increasing material to give the key any mass desired for a particular instrument or a particular operator. In the preferred construction disclosed, this result is achieved by making the individual keys in the form of channels which project beyond the free ends of the levers, each such channel having at its free end a rearwardly and downwardly inclined wall connected with the respective side lianges. This alone gives the key a feeling of solidity. In addition, it constitutes a cavity into which material may be inserted or molded to impart arid desired mass. This Wazll and the side flanges desirably extend downwardly at the rear of the tapered end of the key to give the key a finished appearance.

The present invention contemplate-s that the base have an upstainding finger for each key. The respective fingers 'are desirably struck from material of the base and, between the side flanges of the channel of each key, each respective linger carries a relatively stiff elastomeric guide which precludes lateral displacement of the key in either direction. The guide is important to prevent interference of one key with another.

For accurate and precise limitation of the range of vertical oscillation of the key around the pivotal axis of the lever, I prefer to use Ka different device. I mount a linger directly on the lever adjacent its forward end and I provide -this linger with an elastomeric bumper which engages fixed surfaces of 4the base when the front end of the key is moved either in an upward or downward direction. The upward movement i-s conventionally effected by 'a spring. The downward movement is eliected by the ngers of the operator. The bumper preferably has divergent tapering lins to encounter the upper and lower stops which limit key movement. Because the bumper must be of a nature to positively limit the range, it cannot be unduly soft. The lins make the bumper better cushioned than would be possible with a bumper of different form.

Further in the interest of precision of operation, I provide means whereby the resistance of the key return springs can be adjusted to the precise value desired by any given operation. The respective springs are connected to the baise and have anchorage tongues integral with the key levers. In accordance with the present invention, the respective tongues integrally connected with respective levers are provided with small apertures spaced from the point of such connection and adapted to receive a tool by means of which any tongue may be bent individuallly in one direction or the other to increase or decrease spring bias.

Background of the invention The manner in which the key levers are respectively pivoted to the base is shown in my prior Patent 3,165,965. This patent also shows the spring means for biasing the levers to elevate the forward ends of the keys.

In past devices for guiding such levers and keys, a single fixed guide means engaged by the lever has sometimes been relied upon to perform the functions of limiting the range as well as precluding lateral displacement. Because Isuch single guide means has been subject to accidental or intentional deflection, the two functions are separated in the instant device and the possibility that deflection of one may affect the other is thereby minimized to assure accuracy of movement and range.

It may be also be noted that prior devices have required that the bumpers be cemented in place. This makes repair difiicult or impossible. In the instant device, the relea'sable interlock between the bumpers and the lingers which support them is such as to anchor the respective bumpers securely while still permitting ready replacement when needed.

Description of the invention In the drawings:

FIG. 1 is a fragmentary plan view of a keyboard embodying the invention, portions being removed and other portions shown in section.

FIG. 2 is `a view in transverse section through the keyboard showing in side elevation or longitudinal section some of the parts illustrated in FIG. 1.

FIG. 3 is a fragmentary detail view taken on the line 3 3 of FIG. 2.

FIG. 4 is a fragmentary detail view taken on the line 4 4 of FIG. 2.

FIG. 5 is a fragmentary detail View taken on the line 5 5 of FIG. 2.

IFIG. 6 is an enlarged fragmentary detail view taken on the line 6 6 of FIG. 2.

FIG. 7 isa fragmentary detail view in perspective showing a front portion of the base in the absence of the keys arnd most of the bumpers which restrict the key levers from lateral displacement, only one such bumper being shown.

FIG. 8 is a fragmentary view similar to FIG. 2 showing a modified embodiment of the invention.

FIG. 9 is a view taken in section on the line 9 9 of FIG. 8.

FIG. 10 is a view taken in section on the line 10 10 of FIG. 9.

The base 12 of the improved keyboard embodying the present invention is provided at 14 with an inverted channel which carries a fulcrum pin 16 for the several peripherally slotted rollers 18 with which channel portions of the respective key levers 20 are engaged as shown in my Patent 3,165,965. Each lever is notched at 22 to clear the hub 24 of one of the rollers with which the side anges of the respective channeled lever is engaged. Thus, the key is removably mounted for oscillation unitarily with its mounting roller 18 upon the pintle rod 16. A tension spring 26 connects a linger 28 of the key lever with a linger 30 of the base 12. The -base of the spring tends to re-elevate the front ends of the levers when these are depressed by manipulation of the respective keys mounted thereon.

The lingers 28 are apertured at points spaced slightly toward the free ends of the lingers from the points where such lingers are integrally connected with respective levers. A pointed tool inserted in an aperture may be used to bend the respective finger to increase or decrease the bias of the spring which is connected thereto. By this means the tension on all keys may be adjusted either so that they may all be rendered identical or may be varied to suit the requirements of a particular operator.

The drawings show a black key at 32 and 34 and an intervening white key at 36. Desirably, each key is made of plastic. As best shown in FIGS. 2 and 5, the plastic is channeled to embrace the lever and has an integral internal boss at 38 which is received into a notch 40 at the forward end of the key lever and is flattened, as by heating it, to hold the key and the lever in assembly. The rear end of each key is permanently fixed, as by a rivet 42 to the respective lever 20.

The rollers will normally guide the respective keys for oscillatory movement in a vertical plane. However, to prevent one key from interfering with either of its neighbors, the base 12 has struck from it integral upstanding fingers 44 (FIGS. 6 and 7). Each of these carries an elastomeric bumper or guide 46 Which is closely tted between the flanges 48 and S0 of the respective lever 20 so that the lever cannot move laterally to any appreciable extent but can move freely in a vertical plane. If the movement is accurate in such plane, there need not even be contact between the lever side flanges 48 and 50 and the intervening guide 46.

For the reasons noted above, the present invention contemplates that entirely separate means be used to define the range of oscillation of the free end 52 of the key in a vertical plane. To this end, the forward extremity of each respective lever 20 has fastened to it a linger 54 which extends downwardly well below the margins of the lever flanges 48 and 50 and has its lower end rearwardly extending at 58 and provided with an elastomeric bumper 60 which may be like bumper 46 but is not necessarily the same. Preferably the rearwardly turned lowered extremity 58 of the finger 54 is slightly enlarged or headed at 62 (FIG. 10) so that the elastomeric bumper 60 must be forced over the head 62 to become engaged on the portion 58 of the finger. The opening 64 in the bumper is transversely elongated as shown in FIG. 6 to receive the finger portion 58 (which has a horizontal lateral extent much greater than its vertical height). This orients the bumper in the position shown in FIG. 6.

The bumper 60 has at each of its upper and lower side margins angularly divergent wedge-shaped fins. In FIG. 6 those which diverge upwardly are indicated by reference character 66 while those that diverge downwardly are indicated by reference character 68. Since these fins taper to their respective apices, and since the range limiting contact is established by the apices, such contact is well cushioned and yet is positive (due to firmness of the material) to limit the movement of the respective key to the desired range. The bumper may be made of synthetic rubber of firm substance.

The surfaces engaged by the respective cushions 60 are provided by the base 12 itself or by a reversely channeled member 70 'which is welded at 72 to the under side of the base. The channeled member 70 extends clear across the front of the base and is provided with windowlike openings at 74 (FIGS. 6 and 7) in Which the respective bumpers 60 are disposed. There is ample clearance to make it impossible for the bumpers to touch the side margins of the channeled member 70. In fact, they might be cut if they had relative sliding movement along such margins. However, the side margins are spaced too widely for contact and the top and bottom margins of the respective openings 74 are substantially flush with the respective surfaces 76 and 78 of the channel-shaped member 70, or sufliciently so as to assure that the respective bumpers engage only the flat areas provided by said surfaces 76 and 78.

lf desired, the alternate form of base and channel shown in FIGS. 8 and 9 may be used. In this instance, no windows are neces-sary because -t'he |member 700 is open forwardly throughout its length. The surfaces 760 Iand 780 which are 'disposed in the path of the respective bumpers 60 are formed by the channel flanges and may be planifor-m and continuous.

Whichever embodiment is employed, it will be apparent that the operation of the keys will be smooth and precise. The greasy lubricant used in some keyboards is wholly unnecessary in this device. The permanent interconnection of the keys with the key levers is -a desirable structure tending toward rigidity and strength. The bumper which, in FIG. 6, has the form of a grommet -f-or resisting lateral displacement may, if desired, be replaced with a bumper of -t-he type shown at 60 which is used to limit the range of vertical oscillation.

One very desirable factor is the rmass or body of the free end portion of the key 52. The channeled key is partially closed by a bottom wall insert 80` which is cemented to the side ilanges 82 and 84 of the key beyond Ithe end of the lever 20. This insert may include a downwa-rdly extending lflange at 86. The bottom wall and fiange not vonly impart mass and solidity to the touch but give a finished appearance to the key. Moreover, a cavity is created into which a filler may be introduced or molded if desired. If 'a `separately prefabricated filler is used, it may have a ltransverse aperture to receive a lead weight 92 `if desired. Many players prefer the action of a key `which has a massive free forward end. The instant key may be varied as to its `mass Ito meet all reasonable requirements.

I have cemented into the keys precast fillers, both weighted 'and unweighted by embedded lead or the like. I have also filled the cavities to lany desired extent with synthetic resin putties. Many players like the feeling of solidity which they find in my keys, even when there is no inserted filler.

I claim:

1. A keyboard comprising the combination with a base Iand a key lever pivoted to the base for oscillation in -a vertical plane, of means on the base provided with upper and lower stop means and a finger connected with the key lever and having a rearwardly projecting portion with a somewhat enlarged head, and a bumper mounted thereon and provided with an opening large enough to receive said finger portion but smaller than said head whereby it must be forced over said head to be engaged o-r disengaged from said por-tion.

2. A combination according to claim 1 in which said finger portion and bumper have interengaged means fixing the 'bumper in desired orientation upon said finger portion, the bumper having divergent wedgefshaped fins projecting upwardly and downwardly and constituting the portion of the vbumper which engages the said stop means.

3. A combination according to `claim 2 in which a channel disposed transversely of the base has a web portion Iand upper and lower anges constituting said stop means, said web portion being provided with window-like openings through which the terminal portions of ngers project, the said bumper being disposed within the channel free of lateral contact with Isaid web portion.

l4. A keyboard comprising the combination with ya base and a key lever pivoted to the base for oscillation in a vertical plane, of a first guide means comprising complementary laterally engageable parts lon the key 'lever and ythe 'base fo-r restricting the key lever against lateral movement, and a second and separate guide means comprising complementary vertically engageable parts con` nected with the key lever and with the base for 'limiting the range of oscillation of the key lever upon its pivotal connection with the base, a channel-shaped key of plastic material on said key lever and .having side flanges embracing said lever and having a web seated upon the lever, the end of the lever having a notch and the web yof the key having a boss engaged in the notch, the key being provided remote from the notch with a permanent connection to said lever.

I5. In a keyboard, the combination of a pivoted chiannel-shaped key lever with a central web land laterally spaced side flanges, a base having a fulcrwm means upon which the lever is pivoted and also provided with a spring fanc'horage, the lever being provided forwardly of said fulcrum means with a key and behind said fulcrum means with a finger struck from said web and having an integral connection with ythe lever and a projecting free end :spaced from said connection, a spring connected between the free end of the finger and the spring anchorage of Athe base, said finger having an aperture adapted to receive a pointed tool for bending Ithe finger with respect Ito the lever whereby to vary the tension of the spring connected between the finger and the `anchorage of the base.

References Cited UNITED STATES PATENTS 3,135,153 6/1964 L6 Duca 84-433 3,165,965 1/1965 L6 Duca 84-435 3,026,760 3/1962 .Famer 84-436 FOREIGN PATENTS 286,186 3/1928 Great Britain.

RICHARD B. WILKINSON, Primary Examiner. J. F. GONZALES, Assistant Examiner.

U.S. C1. X.R. 84-439 

